RE: Explosive Upward Forces

For someone to make the claim that a building will globally collapse, before it happens, would need a precedence of some kind. Either it happened before, or the process was proved possible in a lab.

Neither of those have happened, or ever will. So where did they get the idea that the towers would globally collapse? Out of their asses?

Logic and common sense should tell you that they had no grounds to claim global collapse was inevitable.

This is a huge stumbling block that keeps you guys from seeing the reality of the collapses. It also shows you have either done no independent research and are just relying on what you're told, or you don't understand basic physics.

The NIST report only tried to explain away the collapses initiation, they didn't continue in their report and explain how the buildings actually globally collapsed. Because they couldn't. Physics would have to be suspended, and even NIST can't do that.

I am going to reply to several threads at once in here.

First, I can promise you that I DO know what Kinetic Energy is- so don't be a jerk and question my physics background. Maybe you ANOK have heard of the law of conservation. What happens when you drop a rock into a pond. Does the water shoot back up? Hmm....

Second, I didn't say the WTC towers attained freefall - and I didn't calculate freefall speeds. I said near free-fall, and I used the estimated speeds seen in the video - which is about 20MPH slower than freefall.

Third, even if you assume half of free fall, you are still talking about a huge amount of kinetic energy. By the end of the free fall you have all of that weight coming down at its maximum attained speed, and the physics say that the energy released would be somewhere near that of the MOAB.

My WHOLE POINT with this thread was to show, on paper, that the "explosive upward forces" did not have to be caused by controlled explosives.

Whether or not they were used is a question that none of us can truly answer, just guess at.

But the point was, the physics say that the forces were there to cause everything you see in the videos.



[edit on 25-4-2008 by docpoco]

[edit on 25-4-2008 by docpoco]

Originally posted by docpoco
First, I can promise you that I DO know what Kinetic Energy is- so don't be a jerk and question my physics background. Maybe you ANOK have heard of the law of conservation. What happens when you drop a rock into a pond. Does the water shoot back up? Hmm....

If you knew what kinetic energy was then you wouldn't have made the comment you did. And I'm not a jerk just more educated .

A rock thrown into water is nothing like a building collapse, another comment that shows you don't understand the physics of colliding bodies.

The top section did not become completely detached from the rest of the building, how could it? Even if it did the top section was not heavier than the rest of the building. Each floor, according to NIST, could hold 5x it's weight. Do you know what that means and why they do that?

For your hypothesis to work the top would have to have gained a lot of extra weight, where did it come from? Something would have to have completely severed the columns all at the same time and instantly. How did that happen?

Have you looked at Tower Two? How do you explain the tilt and the angular momentum turning into a vertical fall? If it was the top crushing the building how did it work when the top was tilting?
If you know physics you would know that the top should have continued its path according to the law of angular momentum.

The only way it would do what it did was if the undamaged building, bellow the pivot point of the tilt, fell from underneath it. Which is what it did, and you can see it fall faster than the top was moving.
What caused the building to drop, it wasn't the top?

The top section was not sitting true, which it would have to be to cause a straight down global collapse, even if it could which I severely doubt unless physics was postponed for a day. Physics proves that the top should have continued it's angular momentum, which it would have done if it was only the pivot point of the tilt that failed. The whole building failed.
So there is no way that the top crushed the building. Kinetic energy has nothing to do with it.

Please don't get defensive when I say you're not understanding the physics involved, go learn something and then you can argue without making uneducated claims. Calling people names is not a good way to have a discussion on ATS.

[edit on 25/4/2008 by ANOK]

Originally posted by docpoco
Second, I didn't say the WTC towers attained freefall - and I didn't calculate freefall speeds. I said near free-fall, and I used the estimated speeds seen in the video - which is about 20MPH slower than freefall.

Really?

500,000 Tons moving at free fall acceleration would have put the whole thing moving at nearly 100 MPH at the bottom.

So KE = (1/2) x 453592370 kg x 44.2 M/S ^2 = 443078098863.4 Joules

BTW, since you know your physics, you should know that the kinetic energy would be spent some everytime something get's hit by the 500,000 tons.

So, for the first floor to get hit, the kinetic energy would be (assuming freefall): 1/2mv^2

To find velocity:

v^2 = u^2 + 2a(delta x) where u is initial velocity

v^2=2x9.81 m/s^2 x (3.81m)

v= 8.64 m/s

1/2 x 4535923870 kg x 8.64(^2)m/s = 169,302,451,263 Joules.

Or about 2.6 times less than your calculated energy.

BTW, I don't know why people want to equate energy. Force would be the way to go. Which is: F=ma

Which would be about (again for freefall) F= 4535923870 kg x 9.81 m/sec^2 = 44,497,413,164.7 Newtons.

But, again I'll state that the top mass would not be free falling to gravitational acceleration. Since even the buckled columns would hinder gravity's acceleration due to their resistance.

And if you say "Nah, Uh there would be things that fell at freefall", then you'd have to take into account those individual masses and not the combined mass of the top.

Edit: I am not trying to be a jerk. Just wanted you to know that. If I am incorrect in anything, please feel free to correct me. I just ask that people do the same and not be a jerk to me. I'm not implying that you were at all doc, just others in general. I know it can be frustrating when we are wrong (myself included) but it's the only way we learn. Chin up.

[edit on 4/25/2008 by Griff]

[edit on 4/25/2008 by Griff]

[edit on 4/25/2008 by Griff]

I was thinking about the energy approach here in the OP.

Kinetic energy was calculated from the final velocity of approximately 100 mph at the end of the colllapse. This was used as the initial kinetic energy of the top hitting the first undamaged section to conclude that there was enough energy to observe the speed of collapse.

Isn't this kind of circular logic? No offense.

[edit on 4/25/2008 by Griff]

Originally posted by ULTIMA1

Well something brought the buidlings down and most reports like the NIST computer model state it was not plane impact or fire. Plus the fact that no steel building has ever collasped from fire.

Hmmm... it wasn't the plane, it wasn't the fire... and no building has fallen from fire. So how many building have fallen from a plane AND fire? More to the point, how many buildings have stood after a plane impact - of that scale - and fire?

Like the OP I'm not trying to argue for natural collapse. I just don't know, but that line of argument has always bugged me. It's a bit OT, sorry.

To the OP, unless someone has disproved your math, a valuable addition. I can see how massive downward force can cause deflective upward forces as well - haven't studied it but I'd have to agree this is non-proof for demolitions. Anyone care to explain why that's wrong?

Originally posted by Caustic Logic

Originally posted by ULTIMA1

Well something brought the buidlings down and most reports like the NIST computer model state it was not plane impact or fire. Plus the fact that no steel building has ever collasped from fire.

Hmmm... it wasn't the plane, it wasn't the fire... and no building has fallen from fire. So how many building have fallen from a plane AND fire? More to the point, how many buildings have stood after a plane impact - of that scale - and fire?

Like the OP I'm not trying to argue for natural collapse. I just don't know, but that line of argument has always bugged me. It's a bit OT, sorry.

To the OP, unless someone has disproved your math, a valuable addition. I can see how massive downward force can cause deflective upward forces as well - haven't studied it but I'd have to agree this is non-proof for demolitions. Anyone care to explain why that's wrong?

Empire State Building was hit by a b-25 bomber in the 40's. Albeit it was moving slower, however the WTC was specifically designed for a plane travelling at the speeds of the planes on 9/11.

reply to post by talisman


ya, das ist true. i just read something about that - the elevator cable was severed, two actually, and an operator was saved only by coiled cable and air cushion at the bottom of the shaft, though she was badly injured.

I don't know the differences on construction between the bldgs, plane weight, speed, etc... I do hear the WTCs were designed to withstand a 727 impact. Not sure about 767, or if the design actually worked. These seem to be taken as givens...

I suspect there are some very interesting reasons that blueprints and exact schematics are still withheld. But I'm also fairly ignorant on the subject.